Leonard said: "With this new movement for real change, energised with this new generation helping to lead it, but founded on our old and enduring idealism too - that is the unity we can rally around, not simply a call for unity but around a renewed unity of purpose.

"And our shared purpose is clear, to build again, to win again.

"So that our purpose today is not just electing a leader. My aim is to be the next Labour First Minister of Scotland."

The new Scottish party leader also "zero tolerance" of sexism, misogyny and sexual harassment.

"We need to change the political culture," Leonard said, as he vowed to set up an independent route for complaints of this nature.

The remarks come after ex-interim leader Alex Rowley was suspended from Labour on Wednesday over accusations of sending a string of abusive messages and controlling behaviour by his former partner.

Commenting on the result, defeated candidate Sarwar said: "I congratulate Richard on his victory. He has my full and unwavering support, and I look forward to campaigning with him to return a Scottish Labour government.

"Our party will now unite around our new leader because we all share the same burning desire to elect a Scottish Labour government that works for the many, not the few.

He added: "I would like to thank the thousands of members and trade unionists who voted for me, and the hundreds who volunteered to help the campaign.

"I have a deep sense of pride about what we have achieved. I'm sorry I couldn't do it for you, but I look forward to campaigning with you in the weeks, months and years ahead."

'This has been a deeply unedifying election to lead a deeply divided party.'

SNP's Derek Mackay on Scottish Labour leadership contest

SNP business convener Derek Mackay said: "Congratulations to Richard Leonard on becoming the new leader of Scottish Labour.

"The SNP will work with any party to stand up to the Tories - and we hope Mr Leonard will begin by calling on the UK Government to end damaging Tory austerity in this week's budget, halt the botched roll-out of Universal Credit, and protect Scottish jobs and our place in the single market."

"However, despite Mr Leonard's appeals for unity today," he added, "there is no doubt that this has been a deeply unedifying election to lead a deeply divided party.

"Far from engaging in a battle of ideas about how to improve the lives of ordinary people in Scotland, senior Labour figures have instead spent the last three months publicly tearing each other to bits, settling old scores and even suggesting that the campaign is being rigged."

Scottish Conservative leader Ruth Davidson also offered her congratulations, but added: "As Labour's ninth leader since devolution, many people will be wondering whether he will turn out to be another temporary solution to his party's deep seated problems.

"Scottish Labour has spent far too long fighting itself in an endless succession of leadership contests, instead of fighting for a better deal for the people of Scotland.

"The Scottish Conservatives are the only party with the strength and unity to stand up to the SNP and provide the strong opposition our country needs.

"It is unlikely that any new captain will be enough to turn around a Scottish Labour ship that is holed below the waterline."

Leader of the Scottish Liberal Democrats Willie Rennie said: "Stepping up to lead Scottish Labour at any time is a feat but now is like a journey to the North Pole.

"It's cold, has some dangerous predators and nothing is there when you arrive. I wish Richard Leonard well on his journey."

Scottish Greens co-convener Patrick Harvie said: "Congratulations to Richard Leonard on being elected as the new leader of Scottish Labour.

"Aside from internal disciplinary matters, the immediate challenge facing the party is to determine whether it wants to continue with its tactic of shouting from the sidelines and achieving nothing in opposition.

"Alternatively, it can now choose to work constructively with Greens and others to help form a broad, progressive consensus at Holyrood to deliver environmental and social justice in Scotland."

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